Re: New Default GELI kern.geom.eli.threads Value Proposal

On 6/18/26 11:13, vermaden wrote:
> Hi.
> 
> By default GELI uses all threads available on a system - like from nproc(1) output.
> 
> But this 'default' is per device.
> 
> I just came across one of my clients servers to 'check for possible performance improvements' and ... they had 840 GELI threads - 40 threads for each of 21 disks.
> 
> This happened because client left 'kern.geom.eli.threads' on a default value.
> 
> My proposal -> Change the default GELI threads value to number of physical cores.
>                -----------------------------------------------------------------
> 
> So if someone has 20 physical cores with SMT - which means 40 threads - the 20 value should be used.
> 
> It can be made in the source code or as intermediate step - as a config option put automatically in loader.conf(5) or sysctl.conf(5) during installation.
> 
> The nproc(1) is already in Base System ... or 'kern.smp.cores' can be also used as source of information.

amd64 system with 16 2-thread cores (SMT):

# echo $(nproc)
32

(No cpuset based subsetting involved.)

# sysctl kern.smp.cores
kern.smp.cores: 16


aarch64 system with 8 1-thread cores:

# echo $(nproc)
8

# sysctl kern.smp.cores
kern.smp.cores: 8

> 
> Regards,
> vermaden
> 
> 
> 
> 
> 


-- 
===
Mark Millard
marklmi at yahoo.com